Leaky Tunnel is the second stage of Blizzard Boulevard, the 45th sub-chapter of Stories of Legend. It contains a Croakley, 3 Project As, Doge Darks and Tackeys
Battleground
The boss, Croakley, spawns at the beginning with a Project A. 2 more join the battle after 6.6 ~ 8.3s each. Doge Darks start spawning at mild intervals at ~16.6 ~ 20s into the battle. 2 Tackeys spawn in later in the battle; one 40 seconds in and one 70s ~ 73.3s in.
Strategy
Strategy 1
Lineup: Island Cat, Manic Island Cat, Doctor Cat, Drama Cats, Zamboney Cat Manic Mohawk Cat, Manic Eraser Cat, Can Can Cat, Maglev Cat, Awakened Bahamut
Island Cat, Manic Island Cat, Doctor Cat, Drama Cats and Zamboney Cat are a part of combos.
Start off by spawning some meatshields and one Maglev. Once Maglev dies, put out Zambony. Then, start deploying Can Can Cats to kill the first Doge Darks. Then, put out everything except Awakened Bahamut. If the path is clear, send out Awakened Bahamut to damage the Tackeys, Project A.s and Croakley. If timed correctly, the Tackeys should be dead and there should only be 1 or 2 Project A.s left with Croakley. Then stall them until Awakened Bahamut is back again, send him out to kill the last Project A.(s) and Croakley. Then win the level.
Strategy 2 (2 and 3 Star)
Requires all anti-Starred Alien Treasures at Superior
Lineup: Zamboney Cat (30), Awakened Bahamut Cat (40), Slapstick Cats, Lion Cat, Cat Eastwood, Eraser Cat (20+30), Manic Eraser Cat (40), Bombercat (31), Can Can Cat (38+2), Maglev Cat (45)
Zamboney Cat, Slapstick Cats, Lion Cat and Cat Eastwood are present for their combos
Cat Cannon: Thunderbolt
Start off the battle by immediately saving up for and sending out a Maglev Cat, but before you do look to see if the first Project A is slightly in front of Crokley, so it will be able to hit the Project A. and not Croakley. With this Maglev you will be able to one shot the first Project A, upgrade your Worker Cat twice from this and send out Awakened Bahamut and after that spam out your units, including Zamboney, but not the other combo units, note that Awakened Bahamut will get hit at least by one Doge Dark before the meatshields catch up to him, but this doesn't matter even on 3 Star. Awakened Bahamut should be able to knockback Croakley and your units should shortly be able to kill the second Project A before Croakley, and sometimes you can kill both of the same at the same time with one of Awakened Bahamut's strikes. This should all be directly at the enemy base, as the first Maglev made you able to gain a lot of ground, Awakened Bahamut does most of the work during this strategy after the beginning Maglev, the third Project A should die before the first Tackey spawns and and at that point you'll be hitting the base already and thus have virtually won, the only way this could lose is if your Maglev isn't a high enough level to be able to one shot the Project A., or if your RNG is absolutely terrible and you get warped every second from the second and third Project A., thus not being able to hit the base before the first Tackey spawns.